1. Field of the Invention
The invention relates generally to a shaft wall construction comprising of triangular studs used to hold wall panels in place during construction and service life of shaft walls in buildings. The system includes triangular shaped steel studs with one or more layers of gypsum board secured to one side of the triangular shaped steel studs. The triangular steel studs rest in a notched floor and ceiling runner. The one or more layers of gypsum board are then directly attached to a flat side of the triangular stud with properly sized steel screws. This system will typically be used as a shaft wall system or constructed in locations where attachment of gypsum board to both sides of a wall system is not feasible.
2. Background of the Invention
Walls around shafts, such as elevator shafts, were traditionally formed from concrete. Such installations required personnel working inside the shaft to have to wait until the walls were completed, then remove debris and other material from the concrete erection.
As an improvement to the concrete systems, the assignee of the present invention developed a system whereby drywall (such as SHEETROCK brand gypsum board, available from United States Gypsum Corporation of Chicago, Ill.) or other wall panels can be installed from outside the shaft, thereby significantly reducing any scaffolding, and construction debris inside the shaft. Such present day shaft wall assemblies are constructed from one side only, namely outside the shaft. By installing the wall panels from the outside, personnel working inside the shaft no longer needed to wait until the construction was completed to begin their work.
Such systems typically include a pair of J-runners into which a first wall panel is inserted, with the first J-runner along the top of the wall panel and a second J-runner along the bottom as well as both ends of the wall. The J-runner generally is formed from metals, such as steel, and typically includes a first short upstanding section and a second tall upstanding section in a substantially parallel configuration, each forming a substantially right angle with a middle section. Such a configuration allows for a first wall panel (or shaft panel) to be inserted between the upstanding sections to form the interior of the shaft. Additional wall panels can be affixed to the outside of the J-runners, typically to the outer surfaces of the short upstanding sections to form the interior of the room. In typical shaft wall constructions, wall studs, such as C-H studs and E-studs, are used to hold the wall panel in place. This type of construction is described by U.S. Pat. Nos. 3,943,680; 3,940,899; and 4,152,878, all to Balinski, each of which is hereby incorporated by reference in its entirety.
Shaft walls fasteners are not permitted to penetrate from the outermost wall through the assembly according to Fire Tests of Building Construction and Materials, UL 263, Jun. 21, 2011. ASTM E119-15 also limits fastener penetration in shaft wall assemblies. In other words the fastener, such as a nail or screw, cannot penetrate from the outer wall of the shaft wall assembly to the exposed inner space of the shaft. If fasteners do penetrate the assembly, temperature measurements are required to be measured on the heads of the fasteners.
To avoid fastener penetration into exposed inner space of the shaft a conventional shaft wall assembly employs a C-H stud 10 as shown in FIG. 1. FIG. 2 shows a perspective view of an embodiment of such a shaft wall assembly 1 employing the C-H studs 12 and the first and second J-runners 10, 11 to hold the inner and outer walls in place. The first J-runner 10 and the second J-runner 11 are installed in a substantially parallel relationship as well as right and left ends which are not shown, with multiple C-H studs 12 positioned in a substantially perpendicular relationship between the first J-runner 10 and the second J-runner 11. Each J-runner 10, 11 has a horizontal middle wall (section) 6, a shorter vertical wall 2, and a taller vertical wall 4 (FIG. 2). The middle wall 4 forms a substantially planar transverse plane having opposed first and second longitudinal sides each, having a length, and opposed first and second ends, each having a width, wherein the length of each longitudinal side is greater than the width of each end. The shorter vertical wall 2 has a first height H1 and the taller vertical wall 4 has a second height H2, wherein the first height H1 is less than the second height H2. The shorter vertical wall 2 extends to the first height from the first longitudinal side of the middle wall 6. The taller vertical wall 4 extends to the second height from the second longitudinal side of the middle section. The shorter vertical wall 2 and the taller vertical wall 4 are substantially parallel. The middle wall 6, the shorter vertical wall 2 and the taller vertical wall 4 form a generally J-shape.
Positioned between the first J-runner 10 and the second J-runner 11, and between each of the studs 12 is a single shaft liner panel 13. Each shaft liner panel 13 has opposed vertical edges 16 (one shown) inserted into a respective cavity of a stud 12. FIG. 2 shows one edge 16 inserted into a first stud, while the opposed other edge is hidden within a cavity of a second adjacent stud 12. As seen in FIG. 2, wall stud 12 has an in-turned lip 12a and the panel 13 is seated between walls of the stud 12 defining a cavity of the stud 12.
Located outside the J-runners 10 and 11 are a pair of wall boards 14 and 15. When fully installed as an inner surface of the shaft, shaft liner panel 13 forms the inside 28 (FIG. 4) of the shaft, while an outer surface 17 of the wall board 14 forms the interior wall of a room. Additionally, a surface 13a of the shaft liner panel 13 and a surface 19 of the wall board 15 define a wall cavity 20. The wall cavity 20 may be filled with insulation, electrical wiring, plumbing, and/or other building components. Fasteners 35 are selected from screws and nails and do not extend from the outer wall board 14 or 15 to the shaft liner panel 13. Wall boards 14. 15 are typically gypsum wallboard panels.
Typical gypsum wallboard panels and liner panels are made of Type X gypsum wallboard or Type C gypsum wallboard. ⅝″ Type X gypsum board provides one-hour fire protection when used on both sides of a steel partition.
FIG. 3 is a top view of a portion 30 of shaft wall assembly 1 with the J-runners omitted for clarity. This shows fasteners 35 selected from screws and nails do not extend to inside wall liner panels 13. The C-H stud 12 is employed as part of the shaft wall assembly 1 having the inside wall made of liner panels 13 slid into opposed sides of the H-portion of the C-H stud 12 and a visible outer wall having two layers of wall board panels 15, 14. The shaft wall assembly 1 employs fasteners 35 such as screws or nails to fasten panel 15 and panel 14 to C-H stud 10. FIGS. 2 and 3 show the inner wall liner panels 13 define the inside space 28 of the shaft wall assembly 1, separate wall cavity 20 from the inside space 28 of the shaft wall assembly 1, and prevents direct contact of the fasteners 35 with the inside space 28 of the shaft wall assembly 1.
FIG. 3 only shows one fastener 35 attaching panels 14 and 15 to the C-H stud 12. However, it is apparent from FIG. 2 that some fasteners 35 attach panel 15 to the C-H stud 12 and other fasteners 35 attach both panel 14 and panel 15 to the C-H stud 12.
FIG. 4 shows a modified version 40 of the shaft wall assembly of FIG. 3, wherein the outermost layer of panels 14 is omitted. The inside wall is made of liner panels 13 slid into opposed sides of the H-portion of the C-H stud 12. The visible outside wall is made of one layer of gypsum wallboard panels 15 (one shown) attached to the C portion of the C-H stud 12 by fasteners 35 (one shown) selected from screws or nails. This also shows the fasteners 35 selected from screws and nails do not extend to liner panels 13.
U.S. Pat. No. 7,712,267 to Lehane discloses a modification to the shaft wall assembly of FIG. 2 wherein the first (or lower) J-runner 10 is modified to have one more lifting elements or ledge or both to permit simple centering of studs or shaft walls or both. By providing a lifting member in a lower J-runner, the studs or shaft walls or both can rest upon the lifting member to assist in vertically centering the studs or shaft walls or both when the shaft is fully constructed. Thus, the lifting elements allow for self-centering of the panel 13 between the J-runners 10, 11. FIG. 5 shows an embodiment of a shaft wall assembly employing a J-runner of Lehane having a lifting element 21.
Preferably the lifting elements 21 form a flattened surface (ledge) 22 upon which the studs 12 and/or the shaft liner panel 13 can rest. Generally, shaft liner panel 13 is inserted into the J-runner 10, pushed up the ramping edge 23 until it rests upon the ledge 22 and then slid horizontally until a first vertical edge of the shaft panel 13 is properly seated in a first stud 12. Then the next stud 12 is put into place between the lower J-runner 10 and upper J-runner 11 and pushed against the shaft liner panel 13 to have a second vertical edge of the shaft panel 13 seat in a cavity of the second stud 12. The lifting elements also provide a space 24 to define a drain.
Conventional shaft wall assemblies with C-H studs and panels have many benefits. For example, they are constructed from one side only, fire ratings are applicable from either side, they are proven by years of tests and real world use, and they provide relatively quick construction. However, a disadvantage of conventional shaft wall assemblies with C-H studs and panels is they require liner panels which can be difficult to produce and transport. Also, there is generally a limitation in size and gauge of C-H studs, for example they are employed with 24 inch wide liner panels. It would be beneficial to develop a construction that did not require liner panels.